Tabulator punch

ABSTRACT

A tabulator punch comprises upper and lower crossheads joined together by side plates and a punching head which is displaceably mounted in the upper crosshead and which is connected to a spindle nut mounted on a rotatable threaded spindle. The spindle nut is rotatably mounted in the punching head and has an eccentric the rotation of which is adapted to reciprocate a punching blade and a disc at one end thereof. Disc on the other hand is fixedly connected to the spindle nut and is provided on its outer periphery with a groove which is parallel to the spindle axis and adapted to engage in a guide rail which is also parallel to the spindle and which has spaced-apart notches therein the width of each of these notches being greater than the thickness of the disc.

United States Patent [191 Luhrig et al.

TABULATOR PUNCH AGFA-Gevaert Aktiengesellschaft, Leverkusen, Germany Filed: Mar. 15, 1972 Appl. No.: 234,718

Assignee:

Foreign Application Priority Data Mar. 17, [971 Germany P 21 12 808.5

U.S. Cl. 83/558, 83/562 Int. Cl B26f 1/02, B26d 5/02 Field of Search 83/562, 556, 396,

References Cited UNITED STATES PATENTS 7/1913 Bradstreet 83/562 X 1,629,268 5/1927 Greenberg 83/562 Primary Examiner-J. M. Meister Attorney-Arthur G. Connolly et al.

[57] ABSTRACT A tabulator punch comprises upper and lower crossheads joined together by side plates and a punching head which is displaceably mounted in the upper crosshead and which is connected to a spindle nut mounted on a rotatable threaded spindle. The spindle nut is rotatably mounted in the punching head and has an eccentric the rotation of which is adapted to reciprocate a punching blade and a disc at one end thereof. Disc on the other hand is fixedly connected to the spindle nut and is provided on its outer periphery with a groove which is parallel to the spindle axis and adapted to engage in a guide rail which is also parallel to the spindle and which has spaced-apart notches therein the width of each of these notches being greater than the thickness of the disc.

11 Claims, 10 Drawing Figures PMENTEU BET I 6 ma SHEET 10F SHEET w 4 PATENTEU OCT 16 I973 1 TABULATOR PUNCH This invention relates to a tabulator punch consisting which is connected to a spindle nut adaptedto move on a rotatable spindle isarranged in the upper crosshead.

The spindle nut is rotatably mounted in thepunching head and comprises an eccentric, the rotation of which is adapted to reciprocate punching blades. In the punch according to the invention, therefore, both transverse displacement of the punching head and also thereciprocating movement required for punching are produced by one and the same spindle.

In conventional tabulator punches, transverse displacement of the punching head is produced by a driving spindle. An electrical limit switch which is fixed to the punching head and which is actuated by cams on the crosshead of the punch is adapted to interrupt the drive of the driving spindle and hence transverse displacement. The cams are positioned in accordance with the required punching intervals. When the punching head is stationary, punching is carried out by a pneumatically or hydraulically actuated cylinder. On completion of punching, the punching head is moved forward as described above to the next punching position. In other known tabulator punches, transverse displacem ent between the cams takes place at high speed, the speed being reduced for location in the required punching position. One disadvantage inherent in the tabulator punches described above is that two different energies are required for transverse displacement'and for thepunching movement. Another disadvantage is that both the electrical limit switches for interrupting the transverse movement and also the punching cylinder's have to be supplied through trailing supply lines.

The object of the present invention is to provide a tabulator-punch which only requires one type of energy for transverse displacement and for punching and which eliminates the need for the trailing lines that are so troublesome in permanent operation.

According to the invention, this object is achieved in a tabulator punch of the kind described above by virtue of the fact that one end of the spindle nut which is driven by the spindle-comprises a disc which is fixedly connected to it and which is provided around its outer periphery with an axially parallel groove. This groove engages in a guide rail which is directed parallel to the spindle and which is provided at regular intervals with s notches-.'- The width of these notches is somewhat greater'than the thickness of the aforementioned disc. The intervals between the notches correspond to the required punching positions. If the spindle is set rotating, the guide rail prevents the spindle nut from rotating with it. In this way, the punching head is displaced longitudinally parallel to the guide rail. If the disc with its groove comes into the range of a notch in the guide rail, thespindle nut then rotates with the spindle. Accordingly, the longitudinal movement of the punching head is interrupted. Through the rotation of the spindle nut,'the eccentric connected to'it presses a pushrod to which the punching blade is fixed downwards and thus carries out the required punching operation. After one full revolution of the spindle nut, the guide rail reengages in the groove of the disc and the punching head continues its longitudinal movement to the next notch inthe guide rail.

According to a further development of the invention, several guide rails with notches for different punching intervals are fixed to a rotatably mounted shaft. If it is desired to change from one punching interval to another, the shaft with the guide rails is simply rotated until the guide rail with the requisite punching intervals engages in the groove of the aforementioned disc.

One possible disadvantage of the tabulator punc'h according to the invention is that thepunching head can be guided away over a notch without carrying out a punching operation. Conversely, it can also happen that several punching operations are carried out in one and the same position. These disadvantages can be obviated by specially shaping the notches and the disc on the spindle nut. This special shape is characterised by the fact that the notches are bevelled or rounded on that side from which the disc rotates into the notch. Thus, when the disc runs into the notch, rotation of the spindle is partly transmitted to the spindle nut. Parallel with the increase in the rotation of the spindle nut, the longitudinal speed of the punching head is reduced by the corresponding amount or falls continuously to zero. Accordingly, the effect of bevelling the notches is that the punching head approaches the notches at reduced speed. I

A further improvement in the invention relates to the shaping of the disc arranged on the spindle nut. One of the end faces of the disc is reduced in thickness by an amount b after the groove, whilst on its other end face it comprises immediately adjacent the groove a short projection of the same thickness b. The lengths of the reduction in thickness b and of the projection, as measured at the periphery of the disc, are adapted to one another in such a way that the disc does not jam in the notch during rotation. By shaping the disc in this way, it re-engages the guide rail through its groove after one revolution so that the punching head continues its longitudinal movement.

The advantages of the invention are embodied in the fact that the punching programme is purely mechanical. There is no need for electrical or hydraulic feed lines to the punching head so that the tabulator punch according to the invention is extremely reliable in operation.

One embodiment of the invention is described by way of example in the following with reference to the accompanying drawings, wherein:

FIG. 1 is a general view of a tabulator punch;

FIG. 2 is a cross section of FIG. 1 on the line AB;

FIG. 3 is a partial longitudinal section of FIG. 2' on the line CD; l v FIGS. 4 to 9 individually illustrate the co-operation between the guide rail and the disc; and

FIG. 10 shows a detail of the guide rail.

Thetabulator shown in FIG. 1 consists basically of an upper crosshead 1 (front half removed) and a lower crosshead 2 which are fixedly joined together by side plates 3, 4. A spindle 5 and a spline shaft 6 are rotatably mounted in the side plates 3, 4. The spline shaft 6' crosshead 1. The spline shaft 6 is rotatable at a control grip 15 which has different stop positions. For this purpose, the punching head 10 is pushed sideways until it is adjacent one of the two side plates 3, 4, where it leaves the guide rail 7 and instead engages with a short guide rail section 7* fixedly arranged on the side plates. The spline shaft 6 is then freely rotatable. Electrical limit switches 28 prevent the punching head 10 from actually coming into contact with the side plates 3, 4.

FIG. 2 is a cross-section on the line AB of FIG. 1. The punching head 10 is displaceably mounted in the upper crosshead 1. FIG. 2 shows the spline shaft 6 carrying the guide rails 7 (in this case eight in number arranged around the periphery).

FIG. 3 (which is a longitudinal section of FIG. 2 on the line CD) shows the spindle and a spindle nut 9 rotatably mounted in the punching head 10 on two ball bearings (not shown). Between the two bearings, it is in the form of an eccentric 11 and, at one end, in the form of a disc 12. An axially parallel groove 13 is machined into the outer periphery disc 12. The guide rail 7 engages in the groove 13. If the spindle 5 is set rotating, the guide rail 7, engaging in the groove 13, prevents the spindle nut 9 from rotating with it. The spindle nut 9 and the punching head 10 are thus laterally displaced. Notches 14 are provided in the guide rail 7 corresponding in position to the required punching interval, their width being slightly greater than the thickness of the disc 12. When the disc 12 enters the range of a notch 14, it rotates into the slot. Since the spindle nut 9 then rotates with the spindle 5, the lateral movement of the punching head 10 is interrupted.

The eccentric ll cooperates through a pressure roller 17 with a pushrod 19 which is displaceably mounted in the punching head 10 and which converts the rotating movement of the eccentric 11 into a reciprocating movement. Under the effect of the compression spring 25, which is supported on a cover 26, the pushrod 19 is pressed upwards so that the pressure roller 17 is pressed permanently against the eccentric 11. A blade holder 20 is fixed to the lower end of the pushrod 19 by means of a pin 23, the holder supporting a substantially rectangular punching blade 22 by means of screws 21. Soft rubber 24 is arranged inside the substantially rectangular punching blade to protect the sharp edge 22a of blade 22 and act as a core ejector. A suitable punching support 27 on which material 16 to be punched rests is fixed to the lower crosshead 2.

As already mentioned, the spindle nut 9 rotates with the spindle 5 in the vicinity of a notch 14. In doing so, it carries out the required punching of the material 16 under the effect of the eccentric 11 through the pushrod 19 and the punching blade 22. After one revolution, the guide rail 7 re-engages in the groove 13 and the spindle nut 9 and punching head 10 are further laterally displaced. The spindle 5 rotates at a constant speed throughout the entire operation, the rotational movement only being alternately transmitted to the spindle nut 9 and converted into a longitudinal movement through the cooperation of the disc 12 with the guide rail 7.

FIGS. 4 to 9 illustrate the cooperation between the guide rail 7 and the disc 12 in more detail in the form of individual illustrations which show in particular the special shape of the guide rail 7 in the zone in which the disc 12 enters the notches l4, and the special shape of the disc 12 in the zone adjacent the groove 13. FIGS. 4 to 9 are each longitudinal sections through the guide rail 7 showing the disc 12. In the interests of clarity, only that part of the disc 12 of interest to the Specification has been shown in each case, the rest having been left out.

In FIG. 4 (right-hand thread, spindle 5 turning to the right), the disc 12 bears through the groove flank 130 against the side face 7a of the guide rail 7. The disc 12 does not rotate, in other words the spindle nut 9 and hence the punching head 10 move in the longitudinal direction (arrow) of the spindle. When the disc 12 enters the range of the notch 14, it slides with its inclined face 13b on the inclined face 7b of the notch 14 as rotation continues. The longitudinal movement of the disc 12 is thus accompanied by a rotational movement (horizontal arrow), so that since the rotational speed of the spindle remains constant the longitudinal movement is slowed down corresponding to the size of the angle between the surfaces and 7b. Instead of the bevels which are easier to form from the point of view of production it is also possible to provide an arcuate inlet (cf. FIG. 10), so that the longitudinal speed is continuously reduced to zero. Through the bevelled surface 7b, the disc 12 enters the notch 14 to the depth a (cf. FIG. 5), so that the notch 14 cannot be passed over which would be equivalent to the omission of a punching operation. When the disc 12 has reached the notch 14, it rotates into it (cf. FIG. 6). As can be seen from the drawings, the disc 12 is reduced in thickness by the extent b on one side adjacent the groove 13. In addition, a short projection 29, which also has the thickness b, is arranged on the other side of the disc 12 immediately adjacent the groove 13. The lengths of the reduction in thickness and of the projection 29, as measured at the periphery of the disc 12, are adapted to one another in such a way that the disc 12 does not jam in the notch 14. That part of the end face 12a which has been reduced in thickness slides along the flank 7c of the guide rails 7 (pure rotation of the disc 12). When the bevel 12b comes into contact with the guide rail 7, the rotational movement is accompanied by a brief longitudinal movement equivalent in extent to b. The disc 12 has now entered fully into the notch 14, as shown in FIG. 7. It is guided with very little play between the flanks 7c, 7d of the notch 14. The disc 12 then makes one complete revolution (during which the punching is carried out through the eccentric 11 of the spindle nut 9) until the projection 29 comes into contact with the guide rail 7. As a result, the spindle nut 9 is again prevented from rotating and the punching head 10 continues its movement (cf. FIG. 9) to the next notch 14. As a result of the reduction in thickness on one side of the disc 12, and the provision of an equally thick projection on the other side of the disc 12, the spindle nut 9 only ever carries out one punching operation per notch 14. When the spindle 5 rotates in the reverse direction, all movements take place in the reverse direction.

What we claim is:

l. A tabulator punch comprising upper and lower crossheads which are joined together by side plates, and a punching head which is displaceably mounted in the upper crosshead and which is connected to a spindle nut mounted on a rotatable threaded spindle, the spindle nut being rotatably mounted in the punching head and having an eccentric, the rotation of which is adapted to reciprocate a punching blade, and a disc at one end thereof, the disc being fixedly connected to the spindle nut and being provided on its outer periphery with a groove which is parallel to the spindle axis and which is adapted to engage in a guide rail which is also parallel to the spindle and which has spaced-apart notches therein, the width of each of the notches being greater than the thickness of the disc.

2. A tabulator punch according to claim 1, wherein a plurality of guide rails are fixed to a rotatably mounted shaft, each guide rail being provided with notches and being selectively engageable in the groove of the disc by rotation of the shaft.

3. A tabulator punch according to claim 1, wherein the comers entered by said disc at one or more of the notches are bevelled, whereby when the spindle is notched, the rotation of the spindle is partly transmitted to the spindle nut as it moves towards a bevelled notch, the speed of the punching head parallel to the spindle axis being reduced as a result.

4. A tabulator punch according to claim 1, wherein one side of the disc is reduced in thickness on one side of the groove by an amount b and the other side of the disc on the same side of the groove is provided with a short projection of the same thickness b, adjacent the groove, the lengths of the reduction in thickness and the projection being adapted to one another in such a way that the disc can not jam in one of the notches.

5. A tabulator punch'according to claim 2 wherein said notches on each of said guide rails are arranged at spacings which are different from those on others of spindle axis being reduced as a result.

7. A tabulator punch according to claim 1, wherein the corners of said notches contacted by said disc on entering and leaving said notches are relieved to help said disc enter and leave said notches.

8. A tabulator punch according to claim 4, wherein the portion of said disc reduced in thickness on one side and provided with a projection on the other side comprises a small central portion of said disc offset ahead of the remaining section of said disc at said groove, and a connecting portion of said disc smoothly joining said offset portion to the remaining portion whereby said disc is cammed forward as said remaining portion rotates within said notch to cause said offset portion to strike said rail past said notch when said disc rotates in a complete revolution within said notch to terminate rotation of said disc and cause it to resume its displacement by said spindle nut to the next notch on said guide rail.

9. A tabulator punch according to claim 8, wherein said offset has a foot adjacent said groove having a toe disposed ahead of its heel towards'said rail.

10. A tabulator punch according to claim 9, wherein the remaining portion of said disc adjacent said groove has a foot surface having a heel disposed closer to said rail than its toe.

11. A tabulator punch according to claim 10, wherein the comers of said notches entered and left by said disc are relieved to facilitate said entrance and leaving. 

1. A tabulator punch comprising upper and lower crossheads which are joined together by side plates, and a punching head which is displaceably mounted in the upper crosshead and which is connected to a spindle nut mounted on a rotatable threaded spindle, the spindle nut being rotatably mounted in the punching head and having an eccentric, the rotation of which is adapted to reciprocate a punching blade, and a disc at one end thereof, the disc being fixedly connected to the spindle nut and being provided on its outer periphery with a groove which is parallel to the spindle axis and which is adapted to engage in a guide rail which is also parallel to the spindle and which has spacedapart notches therein, the width of each of the notches being greater than the thickness of the disc.
 2. A tabulator punch according to claim 1, wherein a plurality of guide rails are fixed to a rotatably mounted shaft, each guide rail being provided with notches and being selectively engageable in the groove of the disc by rotation of the shaft.
 3. A tabulator punch according to claim 1, wherein the corners entered by said disc at One or more of the notches are bevelled, whereby when the spindle is notched, the rotation of the spindle is partly transmitted to the spindle nut as it moves towards a bevelled notch, the speed of the punching head parallel to the spindle axis being reduced as a result.
 4. A tabulator punch according to claim 1, wherein one side of the disc is reduced in thickness on one side of the groove by an amount b and the other side of the disc on the same side of the groove is provided with a short projection of the same thickness b, adjacent the groove, the lengths of the reduction in thickness and the projection being adapted to one another in such a way that the disc can not jam in one of the notches.
 5. A tabulator punch according to claim 2 wherein said notches on each of said guide rails are arranged at spacings which are different from those on others of said guide rails.
 6. A tabulator punch according to claim 1, wherein the corners entered by said disc at one or more of the notches are rounded, whereby when the spindle is notched, the rotation of the spindle is partly transmitted to the spindle nut as it moves towards a rounded notch, the speed of the punching head parallel to the spindle axis being reduced as a result.
 7. A tabulator punch according to claim 1, wherein the corners of said notches contacted by said disc on entering and leaving said notches are relieved to help said disc enter and leave said notches.
 8. A tabulator punch according to claim 4, wherein the portion of said disc reduced in thickness on one side and provided with a projection on the other side comprises a small central portion of said disc offset ahead of the remaining section of said disc at said groove, and a connecting portion of said disc smoothly joining said offset portion to the remaining portion whereby said disc is cammed forward as said remaining portion rotates within said notch to cause said offset portion to strike said rail past said notch when said disc rotates in a complete revolution within said notch to terminate rotation of said disc and cause it to resume its displacement by said spindle nut to the next notch on said guide rail.
 9. A tabulator punch according to claim 8, wherein said offset has a foot adjacent said groove having a toe disposed ahead of its heel towards said rail.
 10. A tabulator punch according to claim 9, wherein the remaining portion of said disc adjacent said groove has a foot surface having a heel disposed closer to said rail than its toe.
 11. A tabulator punch according to claim 10, wherein the corners of said notches entered and left by said disc are relieved to facilitate said entrance and leaving. 